Mark Whittow and Shane Stokes were both killed on the M40 on Christmas Eve Bernard Guile had been driving for 12 hours trying to get to his son's home Confused Mr Guile, 77, 'did not know where he was', another motorist said

An Oxford University professor and a motor racing expert were killed on Christmas Eve after an elderly former driving instructor with Alzheimer's disease stopped on the motorway.

Bernard Guile had been on the road for more than 12 hours and was driving aimlessly in a confused daze after setting out from Warrington Cheshire to visit his son in Sussex for Christmas.

An inquest into their deaths heard Professor Whittow's car was sent hurtling onto its roof and went flying down the M40 motorway, between junctions 10 and 11.

Several vehicles had already been forced to dramatically swerve away from the car after it came to a sudden halt on the motorway and the professor's Volkswagen Polo was then struck at high-speed by Mr Stokes' Volkswagen Passat, Senior Coroner Darren Salter heard.

Mr Salter said 29-year-old Mr Stokes died almost instantly after receiving a traumatic head injury when his car span out of control after colliding with Professor Whittow's vehicle.

Mr Stokes, who worked at Rockingham racetrack, had been driving with his girlfriend at the time of the crash. She was injured but survived.

The coroner told the inquest in Oxford how several shocked drivers screeched to a halt and fled their vehicles across the debris-covered Tarmac to tend to the injured, where they found Mr Stokes and Prof. Whittow fatally injured.

Mr Stokes, of Poins Close, Heathcote, Warwick, was declared dead at the scene, and Prof Whittow, of Holywell Street, Oxford, was pronounced dead from multiple traumatic injuries in the early hours of December 23.

The collision took place on the M40 northbound, between junctions 10 and 11, on Christmas eve last year.

The inquest heard how Mr Guile was found by another motorist in a confused and dazed state and unable to tell where he was or when it was - when told, he replied 'so not in Wales, then?'.

The inquest heard he had earlier been caught on CCTV footage driving slowly and aimlessly and was involved in minor collisions with road signs and cameras. He had been travelling to Sussex to visit his son Mark, who became increasingly concerned when his father failed to arrive at his home.

Mark and his brother, Andrew Guile, later rushed to their father's bedside in hospital after learning of his dramatic accident, where they found him unusually confused and distressed, Mr Salter told the inquest.

'All that's left to me is what the conclusion should be,' said the coroner.